ORC units are widely usable in industrial purposes, but very rare in residential buildings.
The aim of the Bachelor’s thesis was to investigation solar heated micro ORC unit usage
in the Estonian climate conditions. This thesis consists research and analyses of solar
irradiance for South-Eastern Estonia. Different solar heated sources are defined and
comparison of solar collectors are included in this thesis. Different organic fluids are in
comparison to determine the best solution for the ORC unit under the certain input data.
Electricity production of the ORC unit has been compared to the electricity consumption
of the residential building in this thesis. Solar heated micro ORC unit is insufficient for
the electricity consumption of the residential building. Approximately 50 % electricity
has been covered with the ORC unit in summer. It´s 20...30 % in spring and autumn and
only 5...10 % in winter time. Maximum electrical power was 783 W with this empirical
calculation model of ORC unit with working fluid R245fa. Thermal efficiency was 7 %
and exergy efficiency was 7,5 % at the inlet temperature 80 ºC in evaporator exit. This
calculation model can be the basis of the real test bench. It is believed that further
investigation of collector´s position and tilted angle have the good impact to achieve
better performance for solar heated micro ORC unit.